在不同频率和偏置电场下测量了BaTiO3晶体从三方相到正交相再到四方相相变过程中的介电温谱.基于BaTiO3晶体在电场作用下的偶极子偏转假设和介电特性实验结果,提出BaTiO3各结构相在电场作用下的偶极子偏转路径可以由其相邻相的介电常数随温度的变化特性表现出来.推断出各结构相的偶极子偏转路径,以及偏置电场对偶极子偏转路径的影响.
The temperature-dependence of dielectric-constant of BaTiO3 single crystals in (001 〉 direction is measured under different voltages and frequencies. The crystal experiences rhombohedral-orthorhombic-tetragonal phase transition with the increase of temperature. Base on the assumption of dipoles rotation and the experimental results of dielectric constant, a model is proposed, which holds that the dipoles rotation path can be inferred by the dielectric properties of the adjacent structure phase of BaTiO3. The dipoles rotation paths of rhombohedral, orthorhombic and tetragonal phases are given. The influences of bias dc electric field on the dipoles rotation path are discussed.